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S Schrem R S Freedberg A J Culliford I Kronzon 《Journal of the American Society of Echocardiography》1988,1(4):271-272
Echocardiography is a valuable modality for imaging thrombi and vegetations. Although patients with systemic lupus erythematosus may develop Libman-Sacks endocarditis, in which punctate verrucous plaques are found histologically on valvular endocardial tissue, these lesions are ordinarily too small for ultrasonic imaging. We describe a patient with systemic lupus erythematosus complicated by systemic embolization, who had a large mobile aortic valve thrombus, which was discovered with the aid of echocardiography and was confirmed by surgical resection. 相似文献
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A STUDY OF ANGIOTENSIN II RECEPTORS AFTER CHRONIC INHIBITION OF NITRIC OXIDE SYNTHASE IN THE SPONTANEOUSLY HYPERTENSIVE RAT 总被引:1,自引:0,他引:1
Y. Yang GJ Macdonald KA Duggan 《Clinical and experimental pharmacology & physiology》1996,23(5):441-443
1. Nitric oxide (NO) synthase inhibition, induces a sustained increase in blood pressure and amplifies the pressor response to infused angiotensin II (AngII). This study was designed to investigate the contribution of AngII receptors to the elevated blood pressure and enhanced pressor response to AngII in the spontaneously hypertensive rat (SHR) chronically treated with NG-nitro-l -arginine-methyl ester (l -NAME). 2. Two groups of 13 week old female SHR were housed four to a box. Group I rats received l -NAME for 7 days (2.5 mg/kg per day) in their drinking water. Group II rats received water only. Blood pressure was monitored daily by tail-cuff plethysmography. Plasma AngII was measured by radioimmunoassay. Aortic and uterine receptor binding was determined by saturation analysis using [125I]-Sar8, Ile1)AngII. Data was analysed using the computer program ligand. 3. Mean systolic blood pressure was significantly elevated in rats treated with l -NAME compared with the control group. Plasma AngII concentration was slightly decreased in rats treated with l -NAME compared with control. Densities of both aortic and uterine AngII receptors increased significantly following NO synthase inhibition. Receptor affinity in the aorta decreased in the l -NAME group compared with control. However, uterine AngII receptor affinity was unchanged. 4. We conclude that the increased blood pressure and enhanced pressor responsiveness that occurs with chronic inhibition of NO synthesis may result partly from increased vascular AngII receptor expression. 相似文献
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Incidence of primary opportunistic infections in two human immunodeficiency virus-infected French clinical cohorts 总被引:4,自引:0,他引:4
Yazdanpanah Y Chêne G Losina E Goldie SJ Merchadou LD Alfandari S Seage GR Sullivan L Marimoutou C Paltiel AD Salamon R Mouton Y Freedberg KA 《International journal of epidemiology》2001,30(4):864-871
BACKGROUND: Clinical guidelines for the prevention of opportunistic infections in human immunodeficiency virus (HIV)-infected individuals have been developed on the basis of natural history data collected in the USA. The objective of this study was to estimate the incidence of primary opportunistic infections in HIV-infected individuals in geographically distinct cohorts in France. METHODS: We conducted our study on 2664 HIV-infected patients from the Tourcoing AIDS Reference Centre and the hospital-based information system of the Groupe d'Epidémiologie Clinique du SIDA en Aquitaine enrolled from January 1987 to September 1995 and followed through December 1995. We estimated: (1) CD4-adjusted incidence rates of seven primary opportunistic infections in the absence of prophylaxis for that specific infection or any antiretroviral drugs other than zidovudine; and (2) CD4 lymphocyte count decline. RESULTS: The highest incidence rates for all opportunistic infections studied occurred in patients with CD4 counts < 200/microl. With CD4 counts < 50/microl, the most common opportunistic infections were toxoplasmic encephalitis (12.6 per 100 person-years) and Pneumocystis carinii pneumonia (11.4 per 100 person-years). Mycobacterium tuberculosis was the least common opportunistic infection (< 5.0/100 person-years). Even with CD4 counts > 300/microl, cases of Pneumocystis carinii pneumonia and toxoplasmic encephalitis were reported. The mean CD4 lymphocyte decline per month was 4.6 cells/microl. There was a significant association between HIV risk behaviour and the incidence of cytomegalovirus infection, between calendar year and the incidence of Pneumocystis carinii pneumonia, toxoplasmic encephalitis and Candida esophagitis, and between geographical area and the incidence of Pneumocystis carinii pneumonia and cytomegalovirus infection. CONCLUSIONS: Geographical differences exist in the incidence of HIV-related opportunistic infections. These results can be used to define local priorities for prophylaxis of opportunistic infections. 相似文献